


His

by hyliank8



Category: Undertale (Video Game)
Genre: Dom/sub Undertones, Ecto-Vagina (Undertale), M/M, Plot What Plot/Porn Without Plot, Praise Kink, Vaginal Fingering, i can't believe i'm using all of these tags
Language: English
Status: Completed
Published: 2019-09-14
Updated: 2019-09-14
Packaged: 2020-11-02 05:08:47
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 263
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20631725
Author URL: https://archiveofourown.org/users/hyliank8/pseuds/hyliank8
Summary: Gaster's a bit possessive of his belongings.





	His

**Author's Note:**

> anyways welcome to sanster hell i've got an enormous stats assignment due in less than three hours so i posted this instead of doing that  
come follow me on [tumblr](https://hyliantimelordin221b.tumblr.com/) if you want, i ramble about sanster a lot

Sans gasped at the curl of Gaster’s fingers, feeling utterly at his partner’s mercy. Gaster was relentless—Sans was so lost in pleasure he wasn’t sure he remembered how it felt _ not _ being joined with Gaster like this. Gaster was holding him close to his chest with one strong arm, standing between Sans’ femurs as Sans sat on his desk, while the fingers of Gaster’s other hand buried within Sans’ depths.

Sans held Gaster closer, reveling in the tight hold his lover had on him. He’d be fine with staying like this forever, braced against the person he loved most in the world.

“Mm, you’re so good, you know that?” Gaster growled into his ear canal. “Such a good boy… my sweet little assistant…”

Sans whined at the possessiveness in Gaster’s voice. Fuck, he loved being called his, loved it when Gaster talked to him like he _ belonged _to him.

“ ‘dings, sh-shit,” Sans gasped, unable to voice a coherent thought.

Gaster curled his fingers upwards once more before moving back to thrusting them in and out at a steady pace. “Tell me who you belong to,” Gaster demanded, moving to bite at Sans’ neck as he shivered from the command. “Tell me.” 

“y-you, gaster, i—” Sans cut off with a cry, pleasure coiling in his gut when Gaster thrust his fingers back in, _ hard_. Gaster’s rough teeth on his vertebrae was making it nearly impossible to think.

“Hmm? I didn’t quiet catch that, assistant,” Gaster said, and Sans could _ hear _ the little smirk in his voice.

“y-you, i belong to you!” he cried.


End file.
